EU's Barnier says wants Brexit talks without 'aggressivity'

The European Union's chief Brexit negotiator sought Thursday to ease tensions between the bloc and Britain, saying a deal was possible if the talks were conducted without "aggressivity".

But in a speech to the Irish parliament, Michel Barnier warned that Britain's departure from the EU would have "consequences", in particular for Ireland, raising the possibility of customs checks on the border with Northern Ireland.

"If we put things in the right order, if we negotiate with mutual respect, without any kind of aggressivity... and if we are open to finding solutions, there is no reason why our strong Europe cannot maintain a strong relationship with the UK," Barnier said.

Among all the EU nations, Ireland has particular concerns about Brexit, focused on its strong trade ties with Britain and also its border with Northern Ireland -- the only EU-UK land border.

"I will work with you to avoid a hard border," Barnier told the joint session of the Houses of Oireachtas in Dublin.

But the Frenchman added: "The UK's departure from the EU will have consequences. We have together the duty to speak the truth.

"Customs controls are part of EU border management, they protect the single market, they protect our food safety and our standards.

"But as I already said many times, nothing in this negotiation should put peace at risk, nothing."

The prospect of reinstalling checkpoints has sparked fears for a resumption of tensions in Northern Ireland, which was plagued by decades of violence over British control until the Good Friday peace agreement in 1998.

Both the British and Irish governments have said they want to avoid this, and Irish Premier Enda Kenny said Thursday it would require a "flexible and imaginative" solution.

British Brexit minister David Davis said in March that technology could prevent the need for physical customs officers.

Barnier repeated that the border issue was one of his three priorities for the Brexit talks, together with the rights of EU citizens living in Britain and London's exit bill.

"We first must make sufficient progress on these points before we start discussing the future of our relationship with the UK. And the sooner this will happen, the better," he said.

"If the conditions are right, a close partnership with the UK is in everybody's interests."

- 'Huge and serious uncertainty' -

The Brexit vote has raised the prospect of a referendum on Northern Ireland reuniting with the Republic of Ireland, a provision which is included in the Good Friday Agreement but would require the consent of the British government.

The EU has said that Northern Ireland would automatically become a European Union member state if it voted to unite with Ireland.

Gerry Adams, leader of the Irish nationalist party Sinn Fein, told Barnier in parliament that Northern Ireland should have "special designated status within the EU" even as the rest of Britain leaves.

"Sinn Fein would like to see a referendum on Irish unity within the next five years," he said.

Speaking after talks with Kenny later on Thursday, Barnier said: "I'm aware of the concerns of the Irish people and I'm ready to find solutions.

"I hope as soon as possible to find agreements on the key points where the decision of the UK to leave the EU has created a huge and serious uncertainty."